Noguera



Jan. 15, 1957 J. NOGUERA DRAFTING APPARATUS FOR TEXTILE FIBRES Filed J1i1y 21, 1952 JQSQPLL Nojutia United States Patent "1 cc DRAFTDIG APPARATUS FOR TEXTILE FIBRES Joseph Noguera, Salford, Manchester, England, assignor to Casablancas High Draft Company Limited, Salford, Manchester, England, a British company Application July 21, 1952, Serial No. 299,988

Claims priority, application Great Britain August 9, 1951 2 Claims. (Cl. 19131) This invention relates to drafting apparatus for textile fibres of the kind employing two superposed endless belt loops having co-operating belt runs serving to guide and feed the fibres being drawn, the belt loops being supported at their rear or inlet ends by transverse driving'rollers and at their front or outlet ends by tensor arms, and being guided laterally by cradle side walls. The tensor arms in such apparatus may form part of a two-pronged tensor or may be entirely separate, and are located one in each belt loop to maintain the front ends of these loops in the correct relative working position, i. e. to form the characteristic yielding delivery nip from which the fibres are drawn by following drawing rollers.

The use of separate tensor arms as distinct from the two-pronged tensor aforementioned, is sometimes advantageous as for instance in cases where very wide belts and correspondingly wide cradles are employed, and the present invention is mainly concerned with improvements in the construction of such separate tensor arms.

It has already been proposed in a prior Casablancas apparatus to utilise tensor arms in the form of substantially flat independent rods which engage in grooves formed in the front ends of the cradle side walls, rods of differing widths being employed to regulate the belt pressure at the delivery nip. In this same apparatus it has also been proposed to provide an alternative means for varying the aforementioned pressure by bending over slightly the front ends of the rods which contact the inner surfaces of the supported loops. In this way, a pair of rodscan occupy a working position in which the -bent edges are directed towards each other causing a considerable pressure at the delivery nip, or by turning the rods end over end, i. e. about a transverse axis, the bent edges can be directed away from each other to lessen the pressure at the delivery nip.

According to the present inventionthere is provided, for use in drafting apparatus of the kind specified, a tensor arm in the form of a flat elongated bar having a supporting neck at each end, shaped for engagement in slots in the respective side walls of the cradle, and having opposite side edges which are parallel to, but at different distances from, the longitudinal axis through the centres of the said supporting necks, the arrangement being such that the said arm can be inserted, from either side of the cradle, into an operative position in the cradle slots in which one said side edge of the arm bears against the inner surface of the associated belt loop and, from the same side of the cradle, can be removed from said' slots, turned about the said longitudinal axis and reinserted into the slots so that the other said edge bears against the belt loop inner surface thereby varying the position of the loop and, consequently, the pressure of the loop on the fibres. One of the ends of the bar is preferably pointed to facilitate the entry of the bar into its operative position in the cradle slots and the opposite end is preferably in the form of a head which can be readily handled. A number of tensor arms of different sizes will usually be 2,777,168 Patented Jan. 15, 1957 provided so that the pressure of the belt loops can be varied over a considerable range, and the head of .each arm may conveniently have a form of visual marking to enable the arm size to be readily identified.

In order, that the invention may be clearly understood and readily carried into effect, two embodiments thereof will now be described in detail, with reference to the accompanying drawings in which:

Figure l is a part-sectional side elevation of a two belt drafting apparatus, the forward ends of both belt loops tensor arm in accordance with the invention,

Figure 5 is a front elevation corresponding to Figure 4 but with the endless belts omitted, and Figure 6 is a plan view of a tensor arm as shown in Figures 4 and 5,

In Figures 1 to 3 of the drawings an embodiment of the invention is illustrated which is suitable for use with a drafting apparatus having two comparatively wide superposed belt loops 1 and 2 which are supported at their rear ends respectively on driving rollers 3 and 4 and guided laterally by spaced parallel side walls 5. The walls 5 are coupled together in known manner by transverse members 6 to form a cradle. The forward ends of the belt loops 1 and 2 are each supported by an adjustable tensor arm 7, the tensor arms in turn being supported in appropriate slots 511 formed in the leading edges of the cradle side walls 5.

Each tensor arm 7 is in the form of an elongated bar member having parallel side edges 7a and 7b which are curved or arcuate in cross-section. Supporting necks 8 and 9 are provided one near each end of the bar member, these neck portions being co-planar with the bar member but somewhat narrower for engagement in the slots 5a in the cradle side walls 5 as aforesaid. The shaping of the bar 7 is such that the parallel side edges 7a and 7b are at different distances from a longitudinal axis which extends parallel to the side edges and through the centres of the reduced bar supporting necks 8 and 9.

One of the bar ends 10 is extended beyond the adjacent supporting neck portion 8 to form a point at the extremity of the aforesaid longitudinal axis. This pointed end 10v facilitates the entry of the bar into the associated belt loop and its location in the supporting slots in the cradle side walls. The other end of the bar is extended beyond the adjacent supporting neck portion 9 to provide a head or handle 11 at the extremity, the handle being located in a plane perpendicular to the side faces of the bar. The handle 11 may, as illustrated, be of triangular shape in plan and may be marked on each face with a different number to indicate, with reference to the complementary tensor arm, the size of the belt delivery nip, i. e. the gap between the forward ends of the belt loops at the lines of contact of the tensor arms, which will be obtained by using either side edge 7a or 712 of a bar to support the sary merely to lift either or both tensor arms out of the cradle slots from the same side of the cradle, rotate the or each arm through 180 about its longitudinal axis and reinsert into the appropriate slots. By this simple adjustment the opposite side edge of the or each tensor arm will be brought into contact with the inner surface of the associated belt loop to increase or decrease the pressure thereon according to the dimensions of the arm employed.

It will be appreciated that a number of tensor arms having their side edges 7a, 7b spaced from the longitudinal axis as aforesaid by different amounts, may be available to give a wide range of pressures at the delivery nip. Where an adjustable tensor arm is employed to support each belt loop as shown in Figure 1, the heads of the arms may be marked with members arranged to indicate the proportion of the gap which each tensor arm provides so that the total gap is the sum of the two figures appearing uppermost on the heads.

In Figures 4 to 6, there is shown a second embodiment of the invention in which a tensor arm 12 is employed with a two belt drafting apparatus having the upper belt loop 1 supported at the forward end by a fixed tensor 13, the tensor arm 12 being utilized only in association with the lower belt 2. In this form of apparatus the belt loops 1 and 2 are supported at their rear ends, as in the previous apparatus, by driving rollers 3 and 4 but are laterally guided by separate pairs of spaced parallel side walls 14 and 15 which constitute respectively upper and lower cradles. The side walls 14 of the lower cradle are rigidly coupled by transverse members 16 in known manner and are provided with corresponding slots 14a in their leading edges for the reception of the neck portions 17, 17a of the tensor 12. The side walls 15 constituting the upper cradle are closer together than the walls 14 of the lower cradle so as to fit therebetween, as shown in Figures 4 and 5, and are rigidly coupled by the fixed tensor 13. Extending from each end of the tensor 13 beyond the respective sidewalls 15, is a pin 18, these pins 18 being arranged to engage respectively in backwardly extending hook-like extensions 14b provided one at the upper leading corner of each lower cradle side wall 14, as shown in Figure 4.

The tensor 12 is extended at one end to form a point 19 at one extremity of its longitudinal axis as in the previously described embodiment and, at the opposite end is provided with a head or handle 20. This head or handle 20, in the embodiment illustrated, is of solid shallow cylindrical form and may conveniently be marked on each face to indicate the size of the belt delivery nip, provided by the tensor arm in conjunction with the fixed tensor.

It will be appreciated that, whilst the tensor arm of the invention has been illustrated in Figures 4 and as applied to a lower belt loop, While the upper loop is associated with a fixed tensor, the arm may equally Well b applied to the upper belt loop while some other form of tensor is utilized to support the lower loop. Also the fixed tensor may be replaced by some other known form of removable tensor.

The possibility of revolving a tensor arm. about its longitudinal axis to vary the pressure of a belt loop enables the arm always to be inserted and handled from either side of a cradle. This is, of course, a most desirable feature in cases where access to the cradle is restricted or is only convenient from one side of the latter.

'Each pair of slots 5a and 14a constitutes a seat for the tensor arm necks which constitute bearing means or portions. The opposite side edges of the necks constitute first and second bearing means or seatings for cooperating selectively with the seats 5a and 14a to cause ;the bar to exert pressures of different. intensities on the belt.

I claim:

1. A tensor arm for selectively supporting with pressures of different intensities the front end of a belt loop in a drafting apparatus having superposed co-operating belts laterally guided by cradle side plates having slots in the forward ends thereof provided with seats, said arm comprising a flat elongated bar having two longitudinally extending belt guide edges positioned substantially 180 degrees apart and a neck adjacent each end of the .bar and lying in substantially the same plane as the rear and laterally displaced with respect to the longitudinal axis of the bar and positioned laterally inwardly of said guide edges, each neck having opposite side edges positioned substantially 180 degrees apart and at different lateral distances from the longitudinal axis of the bar and from said guide edges and constituting seatings adapted to be selectively brought into seating engagement with the seats in the slots of the cradle side plates upon rotation of the bar through substantially 180 degrees about the longitudinal axis of the bar for selectively causing one guide edge of the bar to exert a pressure of one intensity on the belt and the other guide edge of the bar to exert a pressure of a different intensity on the belt.

2. A tensor arm for selectively supporting with pressures of different intensities the front end of a belt loop in a drafting apparatus having superposed co-operating belts laterally guided by cradle side plates having slots in the forward ends thereof, said arm comprising a flat elongated bar having two longitudinally extending belt guide edges positioned substantially 180 degrees apart and a neck adjacent each end of the bar and lying in substantially the same plane as the bar and laterally ofiset with respect to the longitudinal axis of the bar and positioned laterally inwardly of said guide edges, each neck having opposite side edges positioned substantially 180 degrees apart and on opposite sides of and at different 1 distances from the longitudinal axis of the bar and at different distances from adjacent guide edges and constituting seatings adapted to be selectively brought into seating engagement with the bottoms of the slots in the cradle side plates upon rotation of the bar through substantially degrees about the longitudinal axis of the bar for selectively causing one of said guide edges to exert a pressure of one intensity on the belt and the other of said guide edges to exert a pressure of a dilferent intensity on the belt, said bar having portions adjacent each neck adapted to engage the cradle side plates for limiting longitudinal movement of the bar when the necks are seated in the slots.

References Cited in the file of this patent UNITED STATES PATENTS 1,765,127 Casablancas June 17, 1930 1,917,699 Casablancas July 11, 1933 2,036,318 Casablancas Apr. 7, 1936 2,206,432 Schofield July 2, 1940 FOREIGN PATENTS 662,001 Germany July 2, 1938 

